CLEVELAND, Ohio -- Natural gas consumption has soared during the past couple of weeks of arctic weather and it's a good bet that next month's bill will include a built-in shudder.

Columbia Gas of Ohio estimates delivered gas volumes this week are double what they were during the first week of last January. Dominion Energy of Ohio said gas volumes in its Ohio lines were running as much as 54 percent higher than a year ago.

Average residential bills are expected to increase by about $20, Columbia estimates because of the extremely cold temperatures.

Still, prices per unit of gas for some Ohio consumers are actually falling.

Dominion and Columbia customers who rely on their utility's monthly variable price are now paying, or soon will pay, less per unit of gas they buy this month than they did in December.

And they are paying less than they did a year ago, in January 2017.

These are consumers who have chosen not to sign contracts with independent gas suppliers, most of which do not offer prices that have been consistently as low as the utility-managed prices.

These consumers instead are enrolled in their utility's "standard choice offer" or SCO.

SCO customers are actually buying the gas from a number of independent suppliers that have competed to be in the program through an auction and have agreed to charge the price set by the utility in conjunction with the Public Utilities Commission of Ohio.

But by the end of the day, the news had set off a panic sell-off and a price drop because traders had been projecting a draw-down of 220 billion to 230 billion cubic feet.

The lower amount signaled that day-to-day gas production is high enough to keep storage from being depleted, said analysts. Weather forecasts for a return to normal winter temperatures next week added to the pressure.

The NYMEX February contract price ended the day at $2.87 for the amount of energy in about 1,000 cubic feet of gas, down 13.6 cents.